list_and_eject_disk.c

#include <windows.h>

#if define UNICODE
	#define CreateFile CreateFileW
	#define GetDriveType GetDriveTypeW
	#define GetLogicalDriveStrings GetLogicalDriveStringsW
#else
	#define CreateFile CreateFileA
	#define GetDriveType GetDriveTypeA
	#define GetLogicalDriveStrings GetLogicalDriveStringsA
#endif

BOOL ejectDisk(char driveLetter[])
{
	char tmp[10] = "\\\\.\\";
	HANDLE handle = CreateFile(strcat(tmp, driveLetter), GENERIC_READ, FILE_SHARE_WRITE, 0, OPEN_EXISTING, 0, 0);
	DWORD bytes = 0;
	//DeviceIoControl(handle, FSCTL_LOCK_VOLUME, 0, 0, 0, 0, &bytes, 0);
	//DeviceIoControl(handle, FSCTL_DISMOUNT_VOLUME, 0, 0, 0, 0, &bytes, 0);
	DeviceIoControl(handle, IOCTL_STORAGE_EJECT_MEDIA, 0, 0, 0, 0, &bytes, 0);
	CloseHandle(handle);
	return TRUE;
}

char *substr(const char *inpStr, char *outStr, size_t startPos, size_t strLen) {
	strncpy(outStr, inpStr + startPos, strLen);
	outStr[strLen] = '\0';
	return outStr;
}

void EjectCDROMs()
{
	DWORD dwSize = MAX_PATH;
	char szLogicalDrives[MAX_PATH] = { 0 };
	DWORD dwResult = GetLogicalDriveStrings(dwSize, szLogicalDrives); //szLogicalDrives = C:<null>D:<null>F:<null><null>
	if (dwResult > 0)
	{
		char* szSingleDrive = szLogicalDrives;//Split szLogicalDrives by <null>
		while (*szSingleDrive)
		{
			CHAR drive[3];
			substr(szSingleDrive, drive, 0, 2);
			if (GetDriveType(drive) == DRIVE_CDROM)//DRIVE_REMOVABLE ==> USB //DRIVE_FIXED ==> C: D: //DRIVE_CDROM ==> CDROM
				ejectDisk(drive);
			// get the next drive
			szSingleDrive += strlen(szSingleDrive) + 1;
		}
	}
}


int main(int argc, LPTSTR argv[])
{
	EjectCDROMs();
	return 0;
}